Bibliotheca Latina From the University of Wisconsin. Extensive list of links to Latin texts (classical, medieval, and neo-Latin). Page is entirely in Latin.
The Later Latin Society Latin, classical, medieval and modern; texts, symposia, grammatical aids, Attic Nights of Aulus Gellius, Res Gestae of Augustus Divus, Erasmus, and Philobiblon of Richard de Bury in Latin
Bibliotheca Augustana Index of Latin literature. Navigation is in Latin: you can browse alphabetically or by century. Also includes German, English, and Greek literature.
Lupa Helps for searching for classical texts. Navigation is in Latin.
Perseus Project Latin Texts With accompanying English translations and links to dictionaries, commentaries, grammars, and other tools.
Latin Texts at CELT CELT is a resource for contemporary and historical Irish documents in literature, history and politics. This particular link takes you to their collection of Latin texts.
Project Libellus Free Latin and Greek texts with certain redistribution restrictions.
Corpus Scriptorum Latinorum Online texts from Augustine to Vergil, sorted by author and including links to Latin, English, and foreign language translations.
Latin Vulgate A site for helping to Learn Latin, using the Latin Vulgate as reading material. English + Latin side-by-side.